Termbox.Banana

Introduction

This module is intended to be imported qualified:

import qualified Termbox.Banana as Termbox

👉 Quick start example

This is a program that displays the last key pressed, and quits on Esc:

{-# LANGUAGE LambdaCase          #-}
{-# LANGUAGE ScopedTypeVariables #-}

module Main where

import Reactive.Banana
import Reactive.Banana.Frameworks

import qualified Termbox.Banana as Termbox

main :: IO ()
main =
  Termbox.run moment

moment
  :: Event Termbox.Event
  -> Behavior (Int, Int)
  -> MomentIO (Behavior (Termbox.Cells, Termbox.Cursor), Event ())
moment eEvent _bSize = do
  let
    eQuit :: Event ()
    eQuit =
      () <$ filterE isKeyEsc eEvent

  bLatestEvent :: Behavior (Maybe Termbox.Event) <-
    stepper
      Nothing
      (Just <$> eEvent)

  let
    bCells :: Behavior Termbox.Cells
    bCells =
      maybe mempty renderEvent <$> bLatestEvent

  let
    bScene :: Behavior (Termbox.Cells, Termbox.Cursor)
    bScene =
      (,)
        <$> bCells
        <*> pure Termbox.NoCursor

  pure (bScene, eQuit)

renderEvent :: Termbox.Event -> Termbox.Cells
renderEvent =
  foldMap (\(i, c) -> Termbox.set i 0 (Termbox.Cell c mempty mempty))
    . zip [0..]
    . show

isKeyEsc :: Termbox.Event -> Bool
isKeyEsc = \case
  Termbox.EventKey Termbox.KeyEsc -> True
  _ -> False

Core API

type TermboxEvent = Event

A termbox event. This type alias exists only for Haddock readability; in code, you are encouraged to use

• Event for reactive-banana events
• Termbox.Event for termbox events

run :: (Event TermboxEvent -> Behavior (Int, Int) -> MomentIO (Behavior (Cells, Cursor), Event a)) -> IO a

Run a termbox program with the specified input and output modes.

Given

• the terminal event stream
• the time-varying terminal size (width, then height)

return

• a time-varying scene to render
• an event stream of arbitrary values, only the first of which is relevant, which ends the termbox program and returns from the main action.

Re-exports from termbox

black :: Attr

blue :: Attr

bold :: Attr

cyan :: Attr

green :: Attr

magenta :: Attr

red :: Attr

reverse :: Attr

underline :: Attr

white :: Attr

yellow :: Attr

set :: Int -> Int -> Cell -> Cells

data Attr

Instances

Monoid Attr

Defined in Termbox.Attr

Methods

mempty :: Attr

mappend :: Attr -> Attr -> Attr

mconcat :: [Attr] -> Attr

Semigroup Attr

Defined in Termbox.Attr

Methods

(<>) :: Attr -> Attr -> Attr

sconcat :: NonEmpty Attr -> Attr

stimes :: Integral b => b -> Attr -> Attr

Num Attr

Defined in Termbox.Attr

Methods

(+) :: Attr -> Attr -> Attr

(-) :: Attr -> Attr -> Attr

(*) :: Attr -> Attr -> Attr

negate :: Attr -> Attr

abs :: Attr -> Attr

signum :: Attr -> Attr

fromInteger :: Integer -> Attr

Show Attr

Defined in Termbox.Attr

Methods

showsPrec :: Int -> Attr -> ShowS

show :: Attr -> String

showList :: [Attr] -> ShowS

Eq Attr

Defined in Termbox.Attr

Methods

(==) :: Attr -> Attr -> Bool

(/=) :: Attr -> Attr -> Bool

data Cell

Constructors

Cell !Char !Attr !Attr

Instances

Storable Cell

Defined in Termbox.Cell

Methods

sizeOf :: Cell -> Int

alignment :: Cell -> Int

peekElemOff :: Ptr Cell -> Int -> IO Cell

pokeElemOff :: Ptr Cell -> Int -> Cell -> IO ()

peekByteOff :: Ptr b -> Int -> IO Cell

pokeByteOff :: Ptr b -> Int -> Cell -> IO ()

peek :: Ptr Cell -> IO Cell

poke :: Ptr Cell -> Cell -> IO ()

Show Cell

Defined in Termbox.Cell

Methods

showsPrec :: Int -> Cell -> ShowS

show :: Cell -> String

showList :: [Cell] -> ShowS

Eq Cell

Defined in Termbox.Cell

Methods

(==) :: Cell -> Cell -> Bool

(/=) :: Cell -> Cell -> Bool

data Cells

Instances

Monoid Cells

Defined in Termbox.Cells

Methods

mempty :: Cells

mappend :: Cells -> Cells -> Cells

mconcat :: [Cells] -> Cells

Semigroup Cells

Defined in Termbox.Cells

Methods

(<>) :: Cells -> Cells -> Cells

sconcat :: NonEmpty Cells -> Cells

stimes :: Integral b => b -> Cells -> Cells

data Cursor

Constructors

Cursor !Int !Int

NoCursor

data Event

Constructors

EventKey !Key

EventResize !Int !Int

EventMouse !Mouse !Int !Int

Instances

Show Event

Defined in Termbox.Event

Methods

showsPrec :: Int -> Event -> ShowS

show :: Event -> String

showList :: [Event] -> ShowS

Eq Event

Defined in Termbox.Event

Methods

(==) :: Event -> Event -> Bool

(/=) :: Event -> Event -> Bool

data InitError

Constructors

FailedToOpenTTY

PipeTrapError

UnsupportedTerminal

Instances

Exception InitError

Defined in Termbox

Methods

toException :: InitError -> SomeException

fromException :: SomeException -> Maybe InitError

displayException :: InitError -> String

Show InitError

Defined in Termbox

Methods

showsPrec :: Int -> InitError -> ShowS

show :: InitError -> String

showList :: [InitError] -> ShowS

data Key

Constructors

KeyChar Char

KeyArrowDown

KeyArrowLeft

KeyArrowRight

KeyArrowUp

KeyBackspace

KeyCtrlBackspace

KeyCtrl6

KeyCtrl8

KeyCtrlA

KeyCtrlB

KeyCtrlBackslash

KeyCtrlC

KeyCtrlD

KeyCtrlE

KeyCtrlF

KeyCtrlG

KeyCtrlJ

KeyCtrlK

KeyCtrlL

KeyCtrlN

KeyCtrlO

KeyCtrlP

KeyCtrlQ

KeyCtrlR

KeyCtrlRsqBracket

KeyCtrlS

KeyCtrlSlash

KeyCtrlTilde

KeyCtrlT

KeyCtrlU

KeyCtrlV

KeyCtrlW

KeyCtrlX

KeyCtrlY

KeyCtrlZ

KeyDelete

KeyEnd

KeyEnter

KeyEsc

KeyF1

KeyF10

KeyF11

KeyF12

KeyF2

KeyF3

KeyF4

KeyF5

KeyF6

KeyF7

KeyF8

KeyF9

KeyHome

KeyInsert

KeyPageDn

KeyPageUp

KeySpace

KeyTab

Instances

Show Key

Defined in Termbox.Key

Methods

showsPrec :: Int -> Key -> ShowS

show :: Key -> String

showList :: [Key] -> ShowS

Eq Key

Defined in Termbox.Key

Methods

(==) :: Key -> Key -> Bool

(/=) :: Key -> Key -> Bool

Ord Key

Defined in Termbox.Key

Methods

compare :: Key -> Key -> Ordering

(<) :: Key -> Key -> Bool

(<=) :: Key -> Key -> Bool

(>) :: Key -> Key -> Bool

(>=) :: Key -> Key -> Bool

max :: Key -> Key -> Key

min :: Key -> Key -> Key

pattern KeyCtrl2 :: Key

pattern KeyCtrl3 :: Key

pattern KeyCtrl4 :: Key

pattern KeyCtrl5 :: Key

pattern KeyCtrl7 :: Key

pattern KeyCtrlH :: Key

pattern KeyCtrlI :: Key

pattern KeyCtrlLsqBracket :: Key

pattern KeyCtrlM :: Key

pattern KeyCtrlUnderscore :: Key

data Mouse

Constructors

MouseLeft

MouseMiddle

MouseRelease

MouseRight

MouseWheelDown

MouseWheelUp

Instances

Show Mouse

Defined in Termbox.Mouse

Methods

showsPrec :: Int -> Mouse -> ShowS

show :: Mouse -> String

showList :: [Mouse] -> ShowS

Eq Mouse

Defined in Termbox.Mouse

Methods

(==) :: Mouse -> Mouse -> Bool

(/=) :: Mouse -> Mouse -> Bool

Ord Mouse

Defined in Termbox.Mouse

Methods

compare :: Mouse -> Mouse -> Ordering

(<) :: Mouse -> Mouse -> Bool

(<=) :: Mouse -> Mouse -> Bool

(>) :: Mouse -> Mouse -> Bool

(>=) :: Mouse -> Mouse -> Bool

max :: Mouse -> Mouse -> Mouse

min :: Mouse -> Mouse -> Mouse

data PollError

Constructors

PollError

Instances

Exception PollError

Defined in Termbox.Event

Methods

toException :: PollError -> SomeException

fromException :: SomeException -> Maybe PollError

displayException :: PollError -> String

Show PollError

Defined in Termbox.Event

Methods

showsPrec :: Int -> PollError -> ShowS

show :: PollError -> String

showList :: [PollError] -> ShowS